Simple heat stabilizer 1-80 °C. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / Power regulators, thermometers, heat stabilizers
Comments on the article
The device is universal and is designed to maintain a fixed value of a given positive temperature in the range of +1...80 °C with an accuracy of 0,2 °C.
The heat stabilizer can be used in an artificial incubator for hatching chickens from eggs (+37,5 °C), a drying cabinet (+60 °C), a home bath, or maintain a positive temperature (+2 °C) in an insulated storage for vegetables on a balcony at negative ambient temperature. At the same time, the possible instability of the mains voltage does not affect the operation of the device.
The device is powered by a transformerless circuit (Fig. 1.15) directly from a 220 V network, which can significantly reduce its dimensions.
The principle of operation of the circuit on the D1 comparator is not alienated from special explanations - it is often used in various devices and is described in the literature. A feature of this inclusion of the comparator is the control of the output load by the emitter output of the microcircuit. The use of transistor VT1 improves the operation of the comparator and simplifies the thyristor control circuit.
Any load with a power of not more than 1000 W is suitable as a heater (I used a 500 W "air" heating element - it is more durable than a light bulb heater). If it is required to control a more powerful load, then the VD3 ... VD7 diodes must be used for a larger allowable operating current (for example, D246A, B, D247A, B) and connect an additional thyristor together with another KT940A transistor similarly to the above diagram. The control signal for the second load (it is connected to separate sockets) is removed from the output D1 / 1.
Rice. 1.15 (click to enlarge)
To control a load with a power of more than 1000 W, you can use one thyristor of the T122-20-4 or T122-25-4 type (the last digit in the designation may be more).
Indicators of the operating modes of the circuit are LEDs HL1, HL2. So, when the device is turned on with the toggle switch S2, if the heating element A1 is not connected (or it has burned out), then both LEDs will light up simultaneously, and during normal operation of the device, the glow between the indicators will alternate: when A1 is heated, the red LED HL1 lights up (thyristor is open), when cooling HL2 - green.
In the circuit, a thermistor of the STZ-19 type is used as a temperature sensor (it has small dimensions and weight), but other types are also suitable (in this case, the inertia of thermal stabilization may increase).
For ease of operation of the thermostat, a switch (S1) is used, which allows you to have 5 fixed temperature values and one variable. In the sixth position of the switch, the variable resistor R2 allows you to set any temperature in the specified range.
It is convenient to adjust the most commonly used temperature values with resistors R3, R6 ... R8, R10 (multi-turn, type SP5-2) in the corresponding switch positions.
The circuit uses fixed resistors of type C2-23; variable resistor R2 type SP2-2; capacitor C1-K50-15, C2 - K10-7V; switch S1 type PG2-5-6P2N; toggle switch S2 type ТЗ; connector X1 - RS-4; nests X2, XZ type G4,0.
When manufacturing the structure, it is necessary to provide a heat sink for the VSI thyristor and VD3...VD7 diodes.
The external view of the housing structure is shown in Fig. 1.16. It is made from dielectric materials.
The connecting cable from the X1 socket to the temperature sensor can be up to two meters long and is made with wires twisted together - this will reduce the effect of interference and interference on the input of the circuit.
Fig. 1.16
Publication: cxem.net
See other articles Section Power regulators, thermometers, heat stabilizers.
Read and write useful comments on this article.
<< Back
Latest news of science and technology, new electronics:
Machine for thinning flowers in gardens
02.05.2024
In modern agriculture, technological progress is developing aimed at increasing the efficiency of plant care processes. The innovative Florix flower thinning machine was presented in Italy, designed to optimize the harvesting stage. This tool is equipped with mobile arms, allowing it to be easily adapted to the needs of the garden. The operator can adjust the speed of the thin wires by controlling them from the tractor cab using a joystick. This approach significantly increases the efficiency of the flower thinning process, providing the possibility of individual adjustment to the specific conditions of the garden, as well as the variety and type of fruit grown in it. After testing the Florix machine for two years on various types of fruit, the results were very encouraging. Farmers such as Filiberto Montanari, who has used a Florix machine for several years, have reported a significant reduction in the time and labor required to thin flowers.
... >>
Advanced Infrared Microscope
02.05.2024
Microscopes play an important role in scientific research, allowing scientists to delve into structures and processes invisible to the eye. However, various microscopy methods have their limitations, and among them was the limitation of resolution when using the infrared range. But the latest achievements of Japanese researchers from the University of Tokyo open up new prospects for studying the microworld. Scientists from the University of Tokyo have unveiled a new microscope that will revolutionize the capabilities of infrared microscopy. This advanced instrument allows you to see the internal structures of living bacteria with amazing clarity on the nanometer scale. Typically, mid-infrared microscopes are limited by low resolution, but the latest development from Japanese researchers overcomes these limitations. According to scientists, the developed microscope allows creating images with a resolution of up to 120 nanometers, which is 30 times higher than the resolution of traditional microscopes. ... >>
Air trap for insects
01.05.2024
Agriculture is one of the key sectors of the economy, and pest control is an integral part of this process. A team of scientists from the Indian Council of Agricultural Research-Central Potato Research Institute (ICAR-CPRI), Shimla, has come up with an innovative solution to this problem - a wind-powered insect air trap. This device addresses the shortcomings of traditional pest control methods by providing real-time insect population data. The trap is powered entirely by wind energy, making it an environmentally friendly solution that requires no power. Its unique design allows monitoring of both harmful and beneficial insects, providing a complete overview of the population in any agricultural area. “By assessing target pests at the right time, we can take necessary measures to control both pests and diseases,” says Kapil ... >>
| Random news from the Archive Synthetic nerves work in the light
09.04.2016
Researchers from Oxford have created an artificial analogue of the neural circuit: synthetic cells, packed using a 3D printer in a kind of conductive tissue, were able to conduct an electrical impulse.
Cells, tiny drops of water with a volume of 50-100 picoliters, enclosed in a single-layer lipid membrane. Such drops contained not only water, they also contained DNA with genes encoding transmembrane proteins, and all the necessary apparatus for protein synthesis. Transmembrane proteins synthesized in the "cell" formed a through channel in the membrane - this is how an "intercellular contact" appeared between two drops, through which an electrical signal could slip through. The work of the "nerve chain" depended on lighting - the "cells" also contained a special photosensitive protein, which, under the influence of light, bound to DNA and activated the genes of transmembrane proteins recorded in it.
A dense ordered stacking of droplets was achieved, as mentioned above, using a 3D printer. The very technology of XNUMXD printing from such "cells" has been developed for a long time, but now the authors of the work had to develop a new recipe for them, so that both the "cells" themselves and the molecular machines contained in them for transcription (synthesis of RNA copies to DNA) and translation ( protein synthesis to RNA) after passing through the printer would remain in working condition.
Michael J. Booth and his colleagues believe that the main achievements of Michael Booth and his colleagues are that they managed to build a light switch into the nervous chain, and that the propagation of the impulse was not limited to two "cells", that the signal went further - to the third drop, fourth, tenth and etc. In such an artificial system, it is quite possible to study some patterns of impulse propagation through conductive tissues, but in the future, researchers want to combine artificial cells with real ones.
To do this, two technological problems need to be solved: first, the 3D-printed droplet complexes "live" in an oily environment, while real cells need an aqueous solution; secondly, pore proteins in artificial cells are embedded in a single-layer lipid membrane, while in real cells it is two-layered, and it is not known whether a transmembrane protein pore will form between them. Perhaps the contact between an artificial and a real cell can be organized in the form of a synapse, when a certain space remains between the cell membranes, and the impulse is transmitted using special chemical neurotransmitter molecules.
|
Other interesting news:
▪ Elephant speaking
▪ Headphones Philips Fidelio L2
▪ The crowd has a collective mind
▪ 2004 through the eyes of Intel
▪ WeWi Sol laptop with solar panel
News feed of science and technology, new electronics
Interesting materials of the Free Technical Library:
▪ section of the site Signal limiters, compressors. Article selection
▪ article Second I. Popular expression
▪ article When was the beginning of taxes? Detailed answer
▪ article Viburnum vulgaris. Legends, cultivation, methods of application
▪ article Universal timer on the RIS-controller. Encyclopedia of radio electronics and electrical engineering
▪ article Outdoor lighting. Supply of outdoor lighting installations. Encyclopedia of radio electronics and electrical engineering
Leave your comment on this article:
All languages of this page
Home page | Library | Articles | Website map | Site Reviews
www.diagram.com.ua
2000-2024
Arabic
Bengali
Chinese
English
French
German
Hebrew
Hindi
Italian
Japanese
Korean
Malay
Polish
Portuguese
Spanish
Turkish
Ukrainian
Vietnamese